Abstract
Purpose: Gastroesophageal reflux is a common disease in infants and children. However, effective pediatric pharmacotherapy with omeprazole is limited by the lack of child-friendly dosage forms and physicochemical drawbacks of omeprazole. To provide a cost-effective, one step alternative to conventional enteric coated pellets we developed spray-dried enteric omeprazole microparticles (OME-MP) using O-carboxymethyl chitosan (CMC) and Eudragit® S100 (ES100). Methods: A central composite design was applied to optimize the spray dried OME-MP. The independent variables were the w/w ratios of CMC/OME (0.5, 5) and ES100/OME (0.5, 10). The dependent variables were considered as EE %, and drug release percentage after 10 min and 60 min. The optimized microparticles were characterized for their size, morphology, thermal behavior and in vitro release. Further, an ethanol induce gastric ulcer model in rat was applied to investigate the in-vivo anti-gastric ulcer efficacy of the optimized OME-MP. Results: The optimised formulation with CMC/OME = 1.92 and ES100/OME = 5.30 produced smooth free flowing microparticles with a size range of 5.42 ± 0.9 µm. In vitro testing showed minimal drug release under simulated gastric conditions (<10 % over 2 h), followed by rapid and extensive release in simulated intestinal medium (> 90 %) confirming pH-triggered protection and delivery. In-vivo study revealed OME-MP reduced ulcer severity compared with the commercially available generic omeprazole pellet formulation, and histological assessment supported improved mucosal preservation. Conclusion: This one-step, spray-dried enteric OME-MP platform offers a scalable enteric system for omeprazole and other acid labile drugs, with potential relevance to pediatric oral administration.